Oceanvolt Hybrid Motor

[mcarthur]

Originally Posted by fallingeggs

It has been mentioned that a performance cat is the best case for an electric set up. Just so happens that the owner of Balance Catamarans posted a video about creating an electric 526, which is one heck of a performance cat (and my dream boat if I strike it big!):

https://youtu.be/e0q98-JQPLk

tl;dw: all electric isn’t ready for a cruising boat because storage isn’t dense enough and solar not efficient enough to create the range required or provide the “get out of jail card” of a diesel. And once you add a generator, your weight is at least equal to a “normal” set up, and your cost and complexity are orders of magnitude higher.

Good find and an interesting video.
I'd amend your tl;dw to be "all electric isn’t ready for a cruising sailing boat …".
As he mentions at the end, there's a lot more possibility for a cruising power catamaran with a significant solar array - which is the what the current examples of long range electric cruisers tend to be.
So while there aren't many cruising power catamarans, they do exist hence putting the "sailing" in your statement ...
...and is what we are looking at doing on our boat using a parallel hybrid + 8-9kW array.

[harlem24]

Wow, 8-9kWp is massive.
What boat are you using?
The Balance guy states that they were able to fit about 5kWp on their 526, which is also massive.
Silent Yachts is doing a fully solar powercat that can be fitted out with a genset.
To my knowledge they have 10kWp on the 55 footer and 26kWp on the 80.
But the thing is, what are you doing, when the sun is not shining? A sailboat can still regen while sailing. OV states that they are able to put in 1kW at 8kn per servoprop.

[valhalla360]

Originally Posted by harlem24

Hm, please check your sources, because as stated before the Renault Zoe, the BMW i3 and the Nissan Leaf have the size akku pack with much more kWh.
The Renault startet with 22kWh and is now at 52kWh, the i3 also 22kWh up to 44kWh and the leaf from 24kWh to 62kWh. All three did not change the outside dimensions of the pack. To my knowledge only Nissan changed to cell manufacturer and the cell format.
So the evolution of the NCM technology was so good to double the capacaty in less then 10 years.

I'm not going to research all your examples but for example from an article about the latest Leaf...

The larger battery has added another 347lbs (157kg) to the party.

That doesn't sound like a technology improvement as much as just more battery.

[harlem24]

As stated, Nissan is to my knowledge the only company that changed the internal structure.
Never said, that more capacity doesn't add more weight.
The Zoe gained 50kg, but for doubleling the capacity, I can live with it.
Still the outside dimensions did not change, even with the leaf.

[valhalla360]

Originally Posted by harlem24

As stated, Nissan is to my knowledge the only company that changed the internal structure.
Never said, that more capacity doesn't add more weight.
The Zoe gained 50kg, but for doubleling the capacity, I can live with it.
Still the outside dimensions did not change, even with the leaf.

More weight is due to more battery cells...the fact they started with a box that wasn't full doesn't mean it's more efficient.

[harlem24]

Question is, why do they communitcate that the internal config did not change then?
The Zoe still has 192 cells in 12 modules (8S2P), with 22kWh, 41kWh and 52kWh.
The ouside shell has not been changed as well.

[mcarthur]

Originally Posted by harlem24

Wow, 8-9kWp is massive.
What boat are you using?
The Balance guy states that they were able to fit about 5kWp on their 526, which is also massive.
Silent Yachts is doing a fully solar powercat that can be fitted out with a genset.
To my knowledge they have 10kWp on the 55 footer and 26kWp on the 80.
But the thing is, what are you doing, when the sun is not shining? A sailboat can still regen while sailing. OV states that they are able to put in 1kW at 8kn per servoprop.

Boat is our 50' powercat - so lots of space for panels. 7kW is easy, the next 1-2kW aren't so easy to fit ...

Remember the Balance isn't a powercat - as the video pointed out and I agreed with, every sailboat is going to have trouble because of the shading effect on panels. Most powerboats (powercats = more breadth) don't have shading problem if they change their radar arch position or be careful.

When the sun doesn't shine - just like pretty everyone doing more than 50nm days - we'll either have a diesel genset or alternators + electric motor generating of the main diesels. I never said we would be electric-only!

I certainly agree with those who point out that electric-only boats are a niche for either short-haul, or very expensive long distance (Turanor).

However, in many (fortunate) ways, it doesn't matter what the nay-sayers on here think (not saying you are one of them) - companies are more and more bringing to the market boats that on here would be considered "impossible". Most recent, in the last week or so, is o-yachts, but it is just one of an increasing number. Sure, some of them won't work. But my guess is that you won't be able to bring your diesel into most major non-Med European port cities in, oh, five years. That's not a long time! Since this is largely a US-centric discussion group, I doubt that change matters to most on here... but it can and is being done.

[harlem24]

What I could think of as an aditional Source might be up and coming are fuel cells.
Especially as methanol cell with liquid as power source.
Problem atm is that the devices are not really powerful and quite expansive.
But if you look at efoy one might see where it might go.
Would be possible to get a fc with 1kW power for let's say 4000$/€ I think many people would be interessted.
If it uses bio methanol it would be CO2 neutral, so far better then any diesel gen, since bio diesel is not really worth producing.

[harlem24]

And yes, I also see restrictions coming for leusure crafts in the not to far future in the EU.

[mark_morwood]

Originally Posted by harlem24

Question is, why do they communitcate that the internal config did not change then?
The Zoe still has 192 cells in 12 modules (8S2P), with 22kWh, 41kWh and 52kWh.
The ouside shell has not been changed as well.

The configuration remained the same, but they changed the cells they were using.

My understanding is that there was no dramatic change in battery chemistry/science in that period, though there of course has been continuous incremental improvement. The car manufacturers were just moving to the higher energy density and cost versions that were already being used in laptops (and Teslas).

https://pushevs.com/2020/04/04/compa...eries-in-2020/

Mark.

[harlem24]

Sure, but saying, in the last ten years were no significant changes in batteries for electric cars, is still wrong. Regarding the statement, that especially Tesla is only using laptop batteries and puts thousands in a car, is only valid for the form factor, but not the chemistry. That is quite diffentent to cells put in to laptop batteries.
And the incremantal changes lead to more then double the capacity they startet with.
Okay, still waiting for glass or solid-state-batteries, but that should be the next step.
Daimler said they will start selling those for their electric busses from 2021.
So it will be interessting to see what will come next also to the boating world.

[valhalla360]

Originally Posted by harlem24

Sure, but saying, in the last ten years were no significant changes in batteries for electric cars, is still wrong. Regarding the statement, that especially Tesla is only using laptop batteries and puts thousands in a car, is only valid for the form factor, but not the chemistry. That is quite diffentent to cells but in to laptop batteries.
And the incremantal changes lead to more then double the capacity they startet with.
Okay, still waiting for glass or solid-state-batteries, but that should be the next step.
Daimler said they will start selling those for their electric busses from 2021.
So it will be interessting to see what will come next also to the boating world.

Do you have any evidence that the chemistry has changed doubling the density per standard size cell? I'm talking about an article listing the actual density and chemical changes not the form factor in a car.

I know they are cramming more cells into the cars but haven't seen anything about switching chemistry to double the density of power.

[harlem24]

Hm, if you have the same number of cells, in the same config, in the same packaging, in the same car, but one version has 22kWh and the other has 41kWh, what changed then? The energy density.
There you find a comparison between the same size same config battery of the Renault Zoe.
https://pushevs.com/2016/10/09/renau...ttery-details/

First generation battery:

Total weight is 290 kg (280 kg are quoted in the video, but in every other source is 290 kg)
Total capacity is 25,92 kWh (192 x 36 Ah x 3,75 V = 25,92 kWh)
Available capacity is 23,3 kWh
192 cells, each with 36 Ah nominal capacity and 3,75 V nominal voltage
Total cell weight is 165,12 kg (192 x 0,86 kg = 165,12 kg)


Second generation battery:

Total weight is 305 kg
Total capacity is 45,61 kWh (estimation by knowing the usable capacity)
Available capacity is 41 kWh
192 cells, each with 63,35 Ah nominal capacity (estimation) and 3,75 V nominal voltage
Total cell weight is 180,12 kg (estimation by knowing the total battery weight)

And no, to my knowledge they did not change the overall chemistry, all cells are still NMC cells, but the technology changed over the four years of production.
So they were able to get 63Ah per cell instead of the 36Ah of the generation before.

[harlem24]

And cramming more cells in the same car is the more unusual process.
Afaik only Tesla did it with the Model S 100 and Nissan with the Leaf + 62kWh.

[valhalla360]

Originally Posted by harlem24

Hm, if you have the same number of cells, in the same config, in the same packaging, in the same car, but one version has 22kWh and the other has 41kWh, what changed then? The energy density.
There you find a comparison between the same size same config battery of the Renault Zoe.
https://pushevs.com/2016/10/09/renau...ttery-details/


And no, to my knowledge they did not change the overall chemistry, all cells are still NMC cells, but the technology changed over the four years of production.
So they were able to get 63Ah per cell instead of the 36Ah of the generation before.

You missed my point. Let's ignore cars and how they package the batteries.

Do you have any evidence the cell chemistry has improved by 100%...or even by what percent?